
40
Parts to be replaced
6-7. Initial setting of adjustment values
6-8. Recording and displaying the Iop information
6-9. Temperature compensation offset adjustment
6-10. Laser power adjustment
6-11. Iop NV Save
6-12. Traverse adjustment
6-13. Focus bias adjustment
6-16. Auto gain control output level adjustment
6-6-4. Auto Check
6-2. PRECAUTIONS FOR CHECKING LASER DIODE
EMISSION
To check the emission of the laser diode during adjustments, never
view directly from the top as this may lose your eye-sight.
6-3. PRECAUTIONS FOR USE OF OPTICAL PICK-
UP (KMS-260B/J1N)
As the laser diode in the optical pick-up is easily damaged by static
electricity, solder the laser tap of the flexible board when using it.
Before disconnecting the connector, desolder first. Before connect-
ing the connector, be careful not to remove the solder. Also take
adequate measures to prevent damage by static electricity. Handle
the flexible board with care as it breaks easily.
Optical pick-up flexible board
6-4. PRECAUTIONS FOR ADJUSTMENTS
1) When replacing the following parts, perform the adjustments
and checks with
in the order shown in the following table.
2) Set the test mode when performing adjustments.
After completing the adjustments, exit the test mode.
Perform the adjustments and checks in “group S” of the test mode.
3) Perform the adjustments to be needed in the order shown.
4) Use the following tools and measuring devices.
• Check Disc (MD) TDYS-1
(Parts No. 4-963-646-01)
• Test Disk (MDW-74/GA-1) (Parts No. 4-229-747-01)
• Laser power meter LPM-8001 (Parts No. J-2501-046-A)
or
MD Laser power meter 8010S (Parts No. J-2501-145-A)
• Oscilloscope (Measure after performing CAL of prove.)
• Digital voltmeter
• Thermometer
• Jig for checking BD (MD) board waveform
(Parts No. : J-2501-196-A)
Optical
Pick-up
IC101
IC102
IC151
IC190
IC195
D101
pick-up
flexible board
laser tap
5) When observing several signals on the oscilloscope, etc.,
make sure that VC and ground do not connect inside the oscillo-
scope.
(VC and ground will become short-circuited.)
6) Using the above jig enables the waveform to be checked without
the need to solder.
(Refer to Servicing Note on page 9.)
7) As the disc used will affect the adjustment results, make sure
that no dusts nor fingerprints are attached to it.
Adjustment
Summary of Contents for HCD-VZ50MD
Page 8: ...8 BD CD board BD CD BOARD To repair the BD CD board remove the bottom plate Bottom view ...
Page 57: ...HCD VZ50MD 57 57 7 4 SCHEMATIC DIAGRAM DECK SECTION E Page 64 TO MAIN BOARD 16 ...
Page 64: ...HCD VZ50MD 64 64 7 11 SCHEMATIC DIAGRAM MAIN 1 4 SECTION ...
Page 65: ...HCD VZ50MD 65 65 7 12 SCHEMATIC DIAGRAM MAIN 2 4 SECTION See page 89 for IC Block Diagrams ...
Page 67: ...HCD VZ50MD 67 67 7 14 SCHEMATIC DIAGRAM MAIN 4 4 SECTION See page 89 for IC Block Diagrams ...
Page 71: ...HCD VZ50MD 71 71 7 18 SCHEMATIC DIAGRAM DIGITAL 2 2 SECTION See page 92 for IC Block Diagrams ...
Page 73: ...HCD VZ50MD 73 73 7 20 SCHEMATIC DIAGRAM AMP SECTION ...
Page 77: ...HCD VZ50MD 77 77 7 24 SCHEMATIC DIAGRAM SWITCH SECTION ...
Page 83: ...HCD VZ50MD 83 83 7 32 SCHEMATIC DIAGRAM POWER SUPPLY SECTION ...